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INSTITUT ZA RUDARSTVO I METALURGIJU BOR YU ISSN: 1451-0162
KOMITET ZA PODZEMNU EKSPLOATACIJU MINERALNIH SIROVINA UDK: 622
UDK: 622.764:622.766:622.36:546.31(045)=861
doi:10.5937/rudrad1204197U
Daniela Urošević*, Dragan Milanović*, Srđana Magdalinović*
ISTRAŽIVANJA MOGUĆNOSTI TRETIRANJA POLIMETALIČNE BARITSKE RUDE
GRAVITACIJSKOM
METODOM KONCENTRACIJE**
Izvod
Najčešće primenjivani postupak u pripremi polimetalične rude i
rude barita je gravitacijska koncentracija, kao predtretman
flotacijskoj metodi koncentracije. Ona se zasniva na razlici u
gustinama korisnih i ostalih prisutnih mineralnih komponenata i na
različitim putanjama kojima se kreću zrna različitih gustiina u
gravitacionim mašinama i uređajima.
Sprovedena istraživanja mogućnosti primene gravitacijske
koncentracije na dostavljenoj poli-metaličnoj masivno sulfidnoj
baritskoj rudi, između ostalog, obuhvataju oglede koncentracije na
klatnom stolu na određenim užim klasama krupnoće. Prethodno je
izveden, na reprezentativnom uzorku rude, preliminarni ogled
pliva-tone u teškoj tečnosti-bromoformu.
Nakon procesuiranja na klatnom stolu, dobijeni rezultati su
laboratorijski obrađeni i dati na hemijsku analizu.
Ključne reči: gravitacijska koncentracija, pliva tone analiza,
klatni sto
* Institut za rudarstvo i metalurgiju Bor, Zeleni bulevar 35 **
Ovaj rad je proistekao kao rezultata Projekta TR-33023 „Razvoj
tehnologija flotacijske prerade
ruda bakra i plemenitih metala radi postizanja boljih
tehnoloških rezultata“, koga finansira Ministarstvo za prosvetu,
nauku i tehnološki razvoj Republike Srbije
UVOD
Na klatnom stolu se gravitacijska kon-centracija obavlja u
fluidu voda, gde za uspešnu koncentraciju veliki značaj imaju
posledična segregacija zrna po krupnoći i gustini, izazvana
istovremenim velikim značajem sila trenja i inercijalnih sila
različitog ubrzanja zrna prisutnih na površini ploče stola. Zrna su
različita i po geometrijskom obliku i nivou srastanja sa drugim, u
rudi prisutnim mineralnim for-mama[1].
Kako barit ima veliku gustinu (oko
4,4-4,5 x 103 кg/m3), realno je očekivati da će njegovo
odvajanje od uobičajeno prisutnih jalovih minerala (kvarc, kalcit,
škriljci ... čija se prosečne gustine kreću od 2,5-3,1 x 103 кg/m3)
biti uspešno. Me-đutim, imajući u vidu da se radi o masivno
sulfidno baritnoj rudi, pretpostavlja se, da će se sulfidni
minerali (čija se prosečna gustina kreće u granicama od
6,0-5-4,8-4,6-4,2 x 103 кg/m3) koncentrisati zajedno
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sa baritom, a što će biti utvrđeno nakon izvođenja serije
ogleda, metodom gravitaci-jske koncentracije na klatnom stolu
[2].
P-T analiza, je jedan vid sagledavanja karakteristike mineralne
sirovine u po-gledu raslojavanja tretiranog materijala po gustini
kojim je omogućeno odvajanje lakših, u našem slučaju jalovih
minerala, od dela težih, u našem slučaju korisnih minerala, na
predmetnoj gustini delenja, bromoformu ρ = 2.820 кg/m3. P-T
analiza, se u principu izvodi na seriji različitih gustina ali zbog
trenutno ograničenih mo-gućnosti laboratorije ista je izvedena samo
na gustini bromoforma [3].
Pri izvođenju preliminarnog ogleda P-T analize, pošli smo sa
predpostavkom da će na gustini raslojavanja od 2.820 кg/m3 doći do
masene raspodele. Tako će u plivajuću frakciju otići jalovi
minerali, gustine manje od gustine bromoforma. U konkretnom
slu-čaju, a po osnovu sagledavanja rezultata mineraloške analize
(silikati, kvarciti, po-dređeno karbonati, itd.), dok će se u
tonuću frakciju skoncentrisati sulfidni minerali i barit, imajući u
vidu njihove gustine, znatno veće od gustine bromoforma.
UZORCI
Tretirani su uzorci polimetalične barit-ske rude sa oznakama
"KOP" i "DEPO" Uzorci su pripremljeni u skladu sa standar-dima
laboratorije za uzorkovanje i pripremu uzoraka - akreditovane
Labora-torije za PMS i ispitivanja Instituta za ru-darstvo i
metalurgiju u Boru.
PROCEDURA
Gravitacijska koncentracija na klatnom stolu
Za oglede gravitacijske koncentracije na klatnom stolu u fluidu
voda, prose-javanjem su, iz svedene klase krupnoće, do 100% -3,35
mm, uzorci razvrstani na dve uže klase krupnoće : -3,35 + 1,18 mm i
-1,18 + 0 mm, što dalje znači da su na klatnom stolu, u prvoj
seriji ogleda, treti-rane sledeće klase krupnoće:
Skupna klasa: -3,35 + 0 mm; Izdvojena klasa: -3,35 + 1,18 mm;
Izdvojena klasa: -1,18 + 0 mm. Pošto, rezultati tretiranja ovih
klasa
krupnoće na klatnom stolu nisu bili zado-voljavajući,u drugoj
seriji ogleda, klasa krupnoće -3,35 + 0 mm, je naknadno drobljenjem
i prosejavanjem svedena do krupnoće 100% -1,18 mm, radi postizanja
većeg stepena otvorenosti sirovine i ista je zatim tretirana na
klatnom stolu.
Sa završetkom tretiranja uzorka, na odgovarajućim mestima
klatnog stola (Slika 1) izdvajaju se u odvojenim posu-dama sledeći
proizvodi (prva serija ogleda):
K-koncentrat; M1-međuproizvod; M2-međuproizvod; Jdef-definitivna
jalovina.
Napomena: Zbog malog masenog učešća međuproizvoda M2, u prvoj
seriji ogleda koncentracije izvršeno je spajanje ovog međuproizvoda
i jalovine, koja je ozna-čena kao definitivna jalovina i kao takva
analizirana na navedene elemente.
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M1 JM2
K
Voda Uzorak
Sl. 1. Izdvajanje proizvoda ogleda koncentracije na klatnom
stolu u prvoj seriji ogled
Iz izdvojenih proizvoda nakon od-
vodnjavanja i sušenja, su izuzeti uzorci za hemijsku analizu i
analizirani na sledeće elemente: Cu, Pb, Zn, Fe, Suk, Ssulfidni,
Ssulfatni i BaSO4.
Šema toka druge serije ogleda gra-vitacijske koncentracije na
klatnom stolu, sa mestima doziranja uzoraka i mestima izdvajanja
proizvoda koncentracije data je na slici 2.
M1 JM2
K
Voda Uzorak
M1J
M2
K
Voda Uzorak
` ``
`
U`
Sl. 2. Šema toka druge serije ogleda gravitacijske
koncentracije
Šema obuhvata dva stepena koncen-
tracije. U prvom stepenu koncentracije na
klatnom stolu,dolazi do razdvajanja na sledeće proizvode:
- Koncentrat K; - Međuproizvod M1; - Međuproizvod M2; - Jalovina
.
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Ulaz u drugi stepen koncentracije, uslo-vno nazvanom
"prečišćavanje", predsta-vljaju spojeni proizvodi iz prvog stepena
koncentracije: međuproizvod M1, među-proizvod M2 i jalovina, kako
je i prikazano na Slici 2. Razdvajanjem na klatnom stolu u drugom
stepenu koncentracije dobijaju se sledeći proizvodi:
- Koncentrat K'; - Međuproizvod M1'; - Međuproizvod M2'; -
Jalovina' . Spajanjem koncentrata iz prvog i
drugog stepena koncentracije, dobijamo konačni bilans proizvoda
druge serije ogleda koncentracije, tj. proizvode:
- Koncentrat K; - Koncentrat K'; - (K + K'= Kdef) - Međuproizvod
M1'; - Međuproizvod M2'; - Jalovina'. Preliminarni ogled P-T je
izveden na
sledeći način: suvi uzorak je potapan u ko-nusni sud u kome se
nalazi teška tečnost-bromoform, sa gustinom (2.820 kg/m3), slika 3.
Nakon mešanja i smirivanja tečnosti dolazi do prirodnog
raslojavanja u bromo-
formu na laku (LF, -2820 kg/m3) i tešku frakciju (TF, +2820
kg/m3) gustina. Iste se zatim izdvajaju iz posude. Frakcije gustina
odlaze na dalju obradu koja se sastoji od postupka centrifugiranja
(radi odstranjivanja zaostale teške tečnosti), pa potom sušenja.
Konačno, izvršeno je merenje uzoraka izdvojene teške i lake
frakcije.
Imajući u vidu gustine prisutnih miner-ala u ispitivanoj
sirovini, koja je vrlo kom-pleksnog mineraloškog sastava, a koje su
kako je već napomenuto znatno veće od gustine bromoforma, došlo je
do koncen-trisanja celokupne mase tretiranog uzorka u teškoj
frakciji, odnosno maseno učešće TF iznosi praktično 100%, kod oba
tretirana uzorka "KOP" i "DEPO". Do očekivanog izdvajanja jalovih
minerala u plivajućoj frakciji nije došlo, što se dalje može
pro-komentarisati njihovim srastanjem sa os-talim teškim mineralnim
formama, kao i nedovoljnom otvorenošću sirovine, pose-bno ako se
ima u vidu mineraloški izveštaj koji upućuje da su predmetni uzorci
tipa masivno sulfidno baritne rude sa znatnim masenim udelom
sulfida i barita 60-70% i shodno tome manjim učešćem petrogenih
komponenata.
Sl. 3. Ogled P-T
EKSPERIMENTALNI DEO
Prva serija ogleda
Prikaz rezultata prve serije ogleda gra-vitacijske koncentracije
tretiranih uzoraka, "KOP" i "DEPO", na klatnom stolu, prika-
zan je respektivno u Tabelama (1-6) i na slikama (4-6).
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Tabela 1. Uzorak "KOP" 100% -3,35+0 mm
Tabela 2. Uzorak "KOP" : Tretirana klasa krupnoće -3,35+1,18
mm.
Tabela 3. Uzorak "KOP": Tretirana klasa krupnoće -1,18 + 0
mm.
Sl. 4. Grafički prikaz tehnoloških iskorišćenja u proizvodima
koncentracije na uzorku "Kop", 100% -3,35+0 mm
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Sl. 5. Grafički prikaz tehnoloških iskorišćenja u proizvodima
koncentracije na
uzorku "Kop", tretirana klasa krupnoće -3,35+1,18 mm
Sl. 6. Grafički prikaz tehnoloških iskorišćenja u proizvodima
koncentracije na
uzorku "Kop", tretirana klasa krupnoće -1,18 + 0 mm
Tabela 4. Uzorak "DEPO" 100% -3,35+0 mm
Tabela 5. Uzorak "DEPO": Tretirana klasa krupnoće -3,35+1,18
mm
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Tabela 6. Uzorak "DEPO": Tretirana klasa krupnoće -1,18 + 0
mm
Sl. 7. Grafički prikaz tehnoloških iskorišćenja u proizvodima
koncentracije na uzorku "Depo", 100% -3,35+0 mm
Sl. 8. Grafički prikaz tehnoloških iskorišćenja u proizvodima
koncentracije na uzorku "Depo", tretirana klasa krupnoće.
-3,35+1,18 mm
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Sl. 9. Grafički prikaz tehnoloških iskorišćenja u proizvodima
koncentracije na uzorku "Depo", tretirana klasa krupnoće -1,18+0
mm
Prikaz ostvarenih rezultata druge
serije ogleda gravitacijske koncen-tracije tretiranih uzoraka,
"KOP" i
"DEPO", na klatnom stolu, prikazan je respektivno u Tabelama
(7-13) i na Slikama (10-17).
Tabela 7. Uzorak "KOP": Tretirana klasa krupnoće 100%-1,18+ 0 mm
(prvi stepen koncentracije)
Sl. 10. Grafički prikaz tehnoloških iskorišćenja u proizvodima
koncentracije na uzorku "KOP",
klasa 100% -1,18 + 0 mm (prvi stepen koncentracije)
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Tabela 8. Uzorak "KOP": Tretirana klasa krupnoće 100% -1,18+ 0
mm (drugi stepen koncentracije)
Sl. 11. Grafički prikaz tehnoloških iskorišćenja u proizvodima
koncentracije na uzorku "KOP",
klasa 100% -1,18 + 0 mm (drugi stepen koncentracije)
Tabela 9. Uzorak "KOP": Tretirana klasa krupnoće 100% -1,18+ 0
mm (drugi stepen koncentracije) - U odnosu na ulaz 85,02%
Sl. 12. Grafički prikaz tehnoloških iskorišćenja u proizvodima
koncentracije na uzorku "KOP",
klasa 100% -1,18 + 0 mm (drugi stepen koncentracije). U odnosu
na ulaz 85,02%
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Tabela 10. Uzorak "KOP": Konačni bilans proizvoda koncentracije
tretirane klase krupnoće 100% -1,18+0 mm
Sl. 13. Grafički prikaz tehnoloških iskorišćenja u proizvodima
koncentracije na uzorku "KOP",
klasa 100% -1,18 + 0 mm - Konačni bilans proizvoda
koncentracije
Tabela 11. Uzorak "DEPO" : Tretirana klasa krupnoće 100% -1,18 +
0 mm (prvi stepen koncentracije)
Sl. 14. Grafički prikaz tehnoloških iskorišćenja u proizvodima
koncentracije na uzorku "Depo",
tretirana klasa krupnoće -1,18 +0 mm (prvi stepen
koncentracije)
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Tabela 12. Uzorak "DEPO" : Tretirana klasa krupnoće 100% -1,18+0
mm (drugi stepen koncentracije)
Sl. 15. Grafički prikaz tehnoloških iskorišćenja u proizvodima
koncentracije na uzorku "DEPO",
klasa 100% -1,18 + 0 mm (drugi stepen koncentracije)
Tabela 13. Uzorak "DEPO": Tretirana klasa krupnoće 100% -1,18+0
mm (drugi stepen koncentracije) - U odnosu na ulaz 75,21 %
Sl. 16. Grafički prikaz tehnoloških iskorišćenja u proizvodima
koncentracije na uzorku "DEPO",
klasa 100% -1,18 + 0 mm (drugi stepen koncentracije) –U odnosu
na ulaz 75,21 %
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Tabela 14. Uzorak "DEPO". Konačni bilans proizvoda koncentracije
tretirane klase krupnoće 100% -1,18+0 mm
Sl. 17. Grafički prikaz tehnoloških iskorišćenja u proizvodima
koncentracije na uzorku "DEPO", klasa 100% -1,18 + 0 mm - Konačni
bilans proizvoda koncentracije
REZULTATI I DISKUSIJA
Sagledavanjem ostvarenih rezultata, u prvoj seriji ogleda
gravitacijske koncen-tracije tretiranih klasa krupnoće: 100% -3,35+
0 mm; -3,35+1,18mm i -1,18+0 mm uzoraka "KOP" i "DEPO" na klatnom
stolu, izvodi se zaključak o nemogućnosti adek-vatne valorizacije
korisnih komponenata, prvenstveno sulfidnih minerala i minerala
barita. Ovi rezultati su sasvim sigurno po-sledica
strukturno-teksturnih karakteristika
sirovine, u pogledu srastanja sulfidnih min-erala sa mineralima
jalovine, što je i pot-vrđeno minerološkom analizom. Zapaženo je i
visoko učešće sulfidne faze, kod oba tretirana uzorka. Vrlo mala
zastupljenost slobodnih zrna, kao i visoka zastupljenost složenih
sraslaca i impegnacija, uticalo je na izdvajanje i koncentrisanje
sulfidnih miner-ala zajedno sa baritom u koncentratu i
me-đuproizvodu. Međutim, približno isti kvalitet
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(sadržaj) analiziranih elemenata prisutan je skoro u svim
proizvodima koncentracije u odnosu na ulaz. Time je ujedno
potvrđena konstatacija izneta s’početka ovog dela pasusa, zasnovana
na saznanjima, da se treti-ranjem baritno sulfidne rude, sulfidni
mine-rali koncentrišu zajedno sa baritom, kod svih tretiranih klasa
krupnoće. Očigledno je da ova sirovina, masivno sulfidna baritska
ruda, iskazuje nepogodnost za gravitacijski tret-man klatnim stolom
u smislu izdvajanja nekakvog gravitacijskog predkoncentrata. To su
nedvosmisleno pokazali, iz prve serije ogleda, ostvareni rezultati
na oba tretirana uzorka "KOP" i "DEPO" na svim tretiranim klasama
krupnoće i to: 100% -3,35+ 0 mm; -3,35+1.18mm i -1,18+0 mm.
Praktično to znači, da je dolazilo samo do fizičkog dele-nja masa
bez značajnije koncentracije mine-rala u očekivanim proizvodima,
koncentratu i eventualno prvom međuproizvodu.
Sagledavanjem rezultata u drugoj seriji ogleda koncentracije,
uviđa se ost-varenje većih tehnoloških iskorišćenja u međuproizvodu
(M1'), kod oba tretirana uzoraka. U drugom stepenu koncen-tracije,
na definisanoj klasi krupnoće 100% -1,18 +0 mm, u poređenju sa
ost-varenim tehnološkim iskorišćenjima u prvoj seriji ogleda u
međuproizvodima je veće tehnološko iskorišćenje. Među-tim, u ovom
slučaju je došlo do koncen-trisanja sulfidnih minerala sa baritom u
međuproizvodu, čime nije ostvarena nikakva selekcija istih.
Skupni-konačni bilans proizvoda kon-centracije predstavljen na
Slici 13 i Slici 17, respektivno prema uzorcima nije dao značajne
rezultate. Odnosno, na osnovu tih prikaza tehnoloških iskorišćenja
u pro-izvodima koncentracije kod oba tretirana uzorka „KOP“ i
„DEPO“ može se zaključiti sledeće:
Očigledno je, da se i daljim usitnjavan-jem sirovine ne postiže
dovoljno otva-ranje, a to je obzirom da se radi o složenoj
polimetaličnoj rudi, sa najzastupljenijim
sulfidnim mineralima: piritom, sfaleritom i galenitom,
halkopirit itd., neophodno. To je ujedno i glavni razlog ovako
dobijenih rezultata. No međutim, daljim otvaranjem mineralne
sirovine tj spuštanjem njene krupnoće, izlazi se iz okvira
mogućnosti i primenljivosti gravitacijskih metoda
kon-centracije.
Složenost ovakve mineralne forme i ost-vareni rezultati upućuju
na zaključak da se ova metoda, kao metoda predkoncentracije,
delimično može primeniti na ovoj sirovini samo pod uslovom, da se
kao proizvodi spoje dobijeni koncentrati i prvi međuproiz-vodi
klatnoga stola. Generalno za oba treti-rana uzorka „KOP“ i „DEPO“,
to bi značilo elimnisanje jalove mase reda veličina od 10-15 % dok
bi se na metalima, zavisno od kog metala, gubilo oko 8-12 %. Znači
postupak predkoncentracije bi se kretao u ovim grani-cama, što
zavisno od kapaciteta prerade može imati smisla samo ako su u
pitanju veliki kapaciteti prerade ove sirovine. U protivnom
gravitacijska koncentracija se ne preporučuje kao metod
predkoncentracije flotacijskoj koncentraciji.
ZAKLJUČAK
Metoda gravitacijske koncentracije na klatnom stolu, pri
tretiranju uzoraka "KOP" i "DEPO", nije se pokazala kao metoda
kojom se može izvršiti efikasna predkoncentracija, odnosno
selekcija sul-fidnih minerala, barita i minerala jalovine, uz
zadovoljavajuće tehnološke rezultate. Složenost ovakve mineralne
forme koja se tretira gravitacijskom koncentracijom na klatnome
stolu i ostvareni rezultati upu-ćuju na zaključak da se ova metoda,
kao metoda predkoncentracije, delimično može primeniti na ovoj
sirovini. Za oba tretirana uzorka „KOP“ i „DEPO“, to bi značilo
eliminisanje jalove mase reda veličina od 10-15 % dok bi se na
metalima, zavisno od kog metala, pri tome gubilo oko 8-12 %.
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LITERATURA
[1] J. Pavlica, D. Draškić, Priprema neme-taličnih mineralnih
sirovina, ISBN 86-7352-012-6, Rudarsko-geološki fakultet Beograd,
1997. god.
[2] D. Draškić, Industrijska primena pri-preme mineralnih
sirovina, Rudarsko-geološki fakultet, Beograd 1986. god.
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No 4, 2012. MINING ENGINEERING
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MINING AND METALLURGY INSTITUTE BOR YU ISSN: 1451-0162 COMMITTEE
OF UNDERGROUND EXPLOITATION OF THE MINERAL DEPOSITS UDK: 622
UDK: 622.764:622.766:622.36:546.31(045)=20
doi:10.5937/rudrad1204197U
Daniela Urošević*, Dragan Milanović*, Srđana Magdalinović*
RESEARCH THE POSSIBILITY OF TREATMENT THE POLYMETALLIC BARITE
ORE BY GRAVITY
CONCENTRATION METHOD**
Abstract
The gravity concentration is the most commonly used method in
the preparation of polymetallic ore and barite ore, as a
pretreatment of flotation concentration method. It is based on a
difference in densities of useful and other present mineral
components present and different travel paths of grains with
different densities in the gravity machine and devices.
Conducted research the possibility of gravity concentration use
on submitted polymetallic mas-sive sulfide barite ore, among
others, include the experiments of concentration on a shaking table
on the certain narrow size classes. The preliminary experiment
floating-sinking was previously performed on a representative
sample of ore in a heavy liquid - bromoform.
After processing on a shaking table, the obtained results were
processed in the laboratory and chemically analyzed.
Keywords: gravity concentration, floating-sinking analysis,
shaking table
* Mining and Metallurgy Institute Bor, Zeleni bulevar 35,
[email protected] ** This work is the result of the
Project 33023 "Technology Development of Flotation Processing of
Copper Ore and Precious Metals in Order to Achieve Better
Technological Results" funded by the Ministry of Education, Science
and Technological Development of the Republic of Serbia
INTRODUCTION
Gravity concentration is carried out on a shaking table in the
fluid water, where the resulted segregation of grains in size and
density has a great importance for successful concentration, caused
by great importance of friction forces and inertial forces of
different accelerations of present grains on the surface of table
plate. The grains are different both by geometric shape and level
of intergrowth to the other mineral forms, present in the ore
[1].
As barite has high density (about 4.4-4.5 x 103 kg/m3), it is
reasonable to expect
that its separation from the usual present barren minerals
(quartz, calcite, shale ... whose average densities ranges from
2.5-3.1 x 103 kg/m3) will be successful. How-ever, taking into
account that this is a massive sulfide barite ore, it is assumed,
that sulfide minerals (whose average den-sity ranges from
6.0-5-4.8-4.6-4.2 x 103 kg/m3) will concentrate together with
bar-ite, and which will be determined after performing a series of
experiments, using the gravity concentration method on a shaking
table [2].
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P-T analysis is an overview of charac-
teristics of mineral resources in terms of separation the
treated material per density, which allowed separation of light, in
this case barren minerals, from a part of heavy, in this case, the
useful minerals, on the subject density of separation, bromoform ρ
= 2 820 kg/m3. P-T analysis is normally carried out on a series of
different densi-ties, but due to the currently limited
capa-bilities of laboratory, the same was carried out on density of
bromoform [3].
In performing the preliminary experi-ment of P-T analysis, it
was started with an assumption that the mass distribution will
occur at density separation of 2820 kg/m3. Thus, the barren
minerals, density less than density of bromoform, will go into
floating fraction. In this case, based on a consideration the
mineralogical analysis results (silicates, quartzites, sub-ordinate
carbonates, etc.), while sulfide minerals and barite will be
concentrated in the sinking fraction, taking into considera-tion
their densities, much higher than the density of bromoform.
SAMPLES
Treated samples were polymetallic barite ore, marked "KOP" and
"DEPO". Samples were prepared in accordance with the standards of
laboratory for sampling and sample preparation – the accredited
Laboratories for mineral processing and testing of the Mining and
Metallurgy In-stitute in Bor.
PROCEDURES
Gravity concentration on a shaking table
For the experiments of gravity concen-tration on a shaking table
in the water fluid by sieving from the reduced size class, up to
100 % -3.35%, the samples are classified into two narrower size
classes: -3.35 + 1.18 mm and -1.18 + 0 mm, which also means that
the following size classes were treated in the firsts series of
experi-ments on a shaking table.
Collective class: -3.35 +0 mm; Separated class: -3.35 + 1.18 mm;
Separated class: -1.18 + 0 mm.
Since the treatment results of these size classes on a shaking
table were not satisfactory, in the second series of ex-periments,
the class size -3.35 mm +0, was subsequently crushed and reduced by
sieving to the size class of 100 % -1.18 mm, to achieve higher
degree of openness the raw material and the same is then treated in
a shaking table.
With the completion of sample treat-ment, the following products
(the first se-ries of experiments) are separated on suit-able
positions of shaking table (Figure 1):
K-concentrate; M1-intermediate; M2-intermediate; Jdef-definite
tailings.
Note: Due to small mass participation of intermediate M2,, in
the first series of ex-periments, this product was merged with
tailings, marked as definite tailings, and analyzed as such on the
given elements.
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M1 JM2
K
Voda Uzorak
Fig. 1. Separation the product of concentration experiment on a
shaking table in
the first series of experiments
The samples were taken from sepa-
rated products after dewatering and drying for chemical analysis
and analyzed for the following elements: Cu, Pb, Zn, Fe, Stotal,
Ssulfide, Ssulfate and BaSO4.
Schematic flow of the second series of gravity concentration
experiments on a shaking,table, with places of sample and places of
separation the concentration products is given in Figure 2.
M1 JM2
K
Voda Uzorak
M1J
M2
K
Voda Uzorak
` ``
`
U`
Fig. 2. Schematic flow the second series of gravity
concentration experiments
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Scheme includes two degrees of concentration.
In the first degreee of concentration on a shaking table, there
is a separation into the following products:
- Concentrate K; - Intermediate M1; - Intermediate M2; -
Tailings. Input into the second degree of
concentration, conditionally called "treatment", is present by
merged products from the first degree of concentration:
intermediate M1, intermediate M2 and tailings, as shown in Figure
2. The following products are obtained by separation on a shaking
table in the second degree of concentration:
- Concentrate K'; - Intermediate M1'; - Intermediate M2'; -
Tailings'.
Merging the concentrate from the first and second degree of
concentration, the definite balance of products from the sec-ond
series of concentration experiments is obtained, i.e. the
products:
- Concentrate K; - Concentrate K'; - (K + K'= Kdef) -
Intermediate M1'; - Intermediate M2'; - Tailings'.
The preliminary P-T experiment was car-ried out as follows: dry
sample was immersed in a conical vessel containing the heavy-liquid
bromoform, with density (2.820 kg/m3), Fig-ure 3. After mixing and
calming the liquid, a natural layering of bromoform occur into
light (LF, -2820 kg/m3) and heavy fraction (TF, +2820 kg/m3) of
density. The same is then separated from vessel. Density fractions
go for further treatment consisting of cen-trifugation procedure
(to remove the residual heavy liquids) and then drying. Finally,
the samples of isolated heavy and light fractions were
measured.
Considering the densities of present minerals in tested raw
material, which has very complex mineralogical composition, and
which, as already mentioned, have much higher densities than
bromoform, there was a concentration of the entire weight of
treated sample in heavy fraction, i.e. the mass participation TF is
practically 100% in both treated samples "KOP" and "DEPO". The
expected separation of bar-ren minerals in a floating fraction was
not occurred, what can be further comment to their intergrowth to
other heavy mineral forms, as well as insufficient openness of raw
materials, especially if the minera-logical report is considered
which sug-gests that the subject samples are of mas-sive sulfide
type barite ore with significant mass participation of sulfide and
barite 60-70% and consequently less participa-tion of petrogenic
components
Fig. 3. Experiment P-T
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EXPERIMENTAL PART
The first series of experiments
Presentation the results of the first se-ries of gravity
concentration experiments of treated samples, "KOP" and "DEPO",
on a shaking table, is shown respectively in Tables (1-6) and
Figures (4-6).
Table 1. Sample "KOP" 100% -3.35+0 mm
Table 2. Sample "KOP": Treated size class -3.35+1.18 mm.
Table 3. Sample "KOP": Treated size class -1.18 + 0 mm.
Fig. 4. Graphical presentation the technological recoveries in
concentration
products on a sample "Kop", 100% -3.35+0 mm
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Fig. 5. Graphical presentation the technological recoveries in
concentration products
on a sample "Kop", treated size class -3.35+1.18 mm
Fig. 6. Graphical presentation the technological recoveries in
concentration products
on a sample "Kop", treated size class -1.18 + 0 mm
Table 4. Sample "DEPO" 100% -3,35+0 mm
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Table 5. Sample "DEPO": Treated size class -3.35+1.18 mm
Table 6. Sample"DEPO": Treated size class -1.18 + 0 mm
Fig. 7. Graphical presentation the technological recoveries in
concentration products
on a sample "Depo", 100% -3.35+0 mm
Fig. 8. Graphical presentation the technological recoveries in
concentration products
on a sample "Depo", treated size class -3.35+1.18 mm
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Fig. 9. Graphical presentation the technological recoveries in
concentration products
on a sample "Depo", treated size class -1.18+0 mm
Presentation the realized results of the second series of
gravity concentration experiments of treated samples, "KOP"
and "DEPO", on a shaking table, is shown respectively in Tables
(7-13) and Figures (10-17).
Table 7. Sample "KOP": Treated size class 100%-1.18+ 0 mm (first
degree of
concentration)
Fig. 10. Graphical presentation the technological recoveries in
concentration products on a
sample "KOP", size class 100% -1.18 + 0 mm (first degree of
concentration)
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Table 8. Sample "KOP": Treated size class 100% -1.18+ 0 mm
(second degree of concentration)
Fig. 11. Graphical presentation the technological recoveries in
concentration products on a
sample "KOP", size class 100% -1.18 + 0 mm (second degree of
concentration)
Table 9. Sample "KOP": Treated size class 100% -1.18+ 0 mm
(second degree of concentration) – in relation to the input
85.02%
Fig. 12. Graphical presentation the technological recoveries in
concentration products
on a sample "KOP", size class 100% -1.18 + 0 mm (second degree
of concentration) – in relation to the input 85.02%
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Table 10. Sample "KOP": Final balance of concentration product
of treated size class 100% -1.18+0 mm
Fig. 13. Graphical presentation the technological recoveries in
concentration products on a
sample "KOP", size class 100% -1.18 + 0 mm – Final balance of
concentration product
Table 11. Sample "DEPO": Treated class size 100% -1.18 + 0 mm
(first degree of concentration)
Fig. 14. Graphical presentation the technological recoveries in
concentration products on a
sample "Depo", treated size class -1,18 +0 mm (first degree of
concentration)
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Table 12. Sample "DEPO": Treated class size 100% -1.18 + 0 mm
(second degree of concentration)
Fig. 15. Graphical presentation the technological recoveries in
concentration products on a
sample "Depo", size class 100% -1.18 +0 mm (second degree of
concentration)
Table 13. Sample "DEPO": Treated class size 100% -1.18 +0 mm
(second degree of concentration)- in relation to the input 75.21
%
Fig. 16. Graphical presentation the technological recoveries in
concentration products on a
sample "Depo", size class 100 % -1.18 +0 mm (second degree of
concentration) – in relation to the input 75.21%
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Table 14. Sample "DEPO": Final balance of concentration product
of treated size class 100% -1.18+0 mm
Fig. 17. Graphical presentation the technological recoveries in
concentration products
on a sample "Depo", size class 100 % -1.18 +0 mm Final balance
of concentration product
RESULTS AND DISCUSSION
Reviewing the achieved results in the first series of gravity
concentration ex-periments of treated size classes: 100% + 0 -3.35
mm; -3.35 +1.18 mm and -1.18+0 mm of samples "KOP" and "DEPO" on a
shaking table, it can be concluded about the impossibility of
adequate valorization the useful components, primarily sulfide
minerals and mineral barite. These results are certainly a
consequence of structural-textural characteristics of raw
materials, in terms of intergrowth the sulfide minerals with the
barren minerals, which was con-firmed by mineralogical analysis.
High participation of sulfide phase was also observed in both
treated samples.
A very low presence of free grains, as
well as high presence of complex inter growings and
impregnations has affected the separation and concentration of
sulfide minerals with barite in concentrates and intermediate
product. However, approxi-mately the same quality (content) of
ana-lyzed elements is present in almost all concentration products
compared to the input. This also confirmed the statement from the
beginning of this paragraph, based on the findings that the
treatment of sulfide barite ore results into concentration of
sulfide minerals together with barite in all treated size classes.
Obviously that this raw material, massive sulfide barite ore,
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expresses a disadvantage for gravity treatment by shaking table
in terms of separation some kind of gravitational pre-concentrate.
This is clearly shown by the realized results on both treated
samples "KOP" and "DEPO" in all treated size classes as follows:
100% + 0 -3.35 mm, -3.35+1.18mm and -1.18+0 mm. In prac-tice, this
means that only physical division of masses occurs without
significant con-centration of minerals in the expected products,
concentrate and possibly the first intermediate product.
Reviewing the achieved results in the second series of gravity
concentration experiments, realization of higher techno-logical
recoveries is recognized in an in-termediate (M1'), in both treated
samples. In the second degree of concentration on defined size
class size of 100% -1.18 +0 mm, compared with the realized
techno-logical recoveries in the first series of ex-periments in
intermediate products, the technological recovery is higher.
How-ever, in this case, there was a concentra-tion of sulfide
minerals with barite in in-termediate, which did not achieve any
selection of the same.
The final balance of concentration prod-ucts is presents in
Figures 13 and 17, respec-tively according to the samples, did not
give the significant results. Respectively, based on a review of
those technological recover-ies in the concentration products for
both treated samples "KOP" and "DEPO", the following can be
concluded:
It is obvious that further comminuting of raw material does not
achieve enough openness, and that is because it is a com-plex
polymetallic ore with the most repre-sented sulfide minerals:
pyrite, sphalerite, and galena, chalcopyrite, etc. is necessary. It
is also the main reason for such ob-tained results. But, however,
further open-ing of raw minerals, i.e. lowering of its
coarseness, comes out from the possibili-ties and applicability
of gravity concentra-tion method.
Complexity of such mineral form and the obtained results
indicate to a conclu-sion that this method as the method of
pre-concentration, should be partially used to this raw material
only on a condition that the obtained concentrates and fist
inter-mediates of a shaking table are connected together as
products. Generally, for both treated samples "KOP" and "DEPO", it
would mean the elimination of barren mass of the order of 10-15%,
while the metals, depending on metal type, would lose about 8-12%.
So, the pre-concentration procedure would be moved within these
limits, depending on the processing capacity, what can be
mean-ingful only if it is a case with the process-ing capacity of
this raw material. Other-wise, the gravity concentration is not
rec-ommended as the pre-concentration method of flotation
concentration.
CONCLUSION
Gravity concentration method on a shaking table in treatment the
samples "KOP" and "DEPO", has not proved to be a method for
efficient pre-concentration or selection the sulfide minerals,
barite and barren minerals with satisfactory techno-logical
results.
Complexity of this mineral form which is treated by gravity
concentration on a shaking table and the obtained results in-dicate
to a conclusion that this method as a method of pre-concentration,
can be partially used to this raw material. For both treated
samples "KOP" and "DEPO", it would mean the elimination of barren
mass of the order of 10-15%, while the metals, depending on metal
type, would lose about 8-12%.
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REFERENCES
[1] J. Pavlica, D. Draškić, Non-Metallic Mineral Processing,
ISBN 86-7352-012-6, Faculty of Mining and Geology, Belgrade, 1997
(in Serbian);
[2] D. Draškić, Industrial Use of Mineral
Processing, Faculty of Mining and Geology, Belgrade, 1986 (in
Serbian).